Area of a Circle Segment Given the Central Angle
Definition: The number of square units it takes to fill a
of a circle
Try this Drag one of the orange dots that define the endpoints of the segment.
Note the number of square units it takes to fill it.
The formula to find the area of the segment is given below. It can also be found by calculating the area of
the whole pie-shaped sector and subtracting the area of the
isosceles triangle △ACB.
If you know the segment height
If you know the segment height and radius of the circle you can also find the segment area. See
Area of a Circular Segment given the Segment Height.
Use the calculator below to calculate the segment area given the radius and segments's central angle, using the formula described above
Other circle topics
Equations of a circle
Angles in a circle
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